Sequencing, Expression and Diagnostic Application of the Nucleoprotein Gene of Xinjiang Hemorrhagic Fever Virus

In order to analyze the nucleoprotein (NP) gene of Crimean-Congo hemorrhagic fever virus (CCHFV), viral RNA was amplified by RT-PCR by using the proof-reading DNA polymerase to produce the complete NP gene. The PCR product was sequenced, analyzed for phylogenesis and cloned into the expression vector pE132a and the recombinant plasmid expressed in E. coil BL-21 with high yield. The primarily purified fused protein.was used to coat ELISA plates for the detect antibodies. It was found the similarities between NP gene of BA88166 and other XHFVs in nucleotide level and amino acid contents were very significant, and the NP gene of BA88166 encoded a nucleoprotein with 482 amino acid and a deduced molecular weight (MW) of 54 kDa. Western blot assay showed that the fusion protein expressed in bacteria possessed good antigenicity. The results with ELISA for the detection of the human and animal sera collected in endemic areas were found to be in good accordance to the clinical diagnosis. It concluded that the relations of NP genes of XHFV BA88166 and other XHFVs appeared to be evolutionally close. The methodologies established in this study were accurate, specific, rapid and reproducible for the clinical examinations and epidemiological survey.